What's in a 'master kit': pinion bearings, carrier bearings, races, crush sleeve, seals, shims, marking compound, hardware. Buy a master — don't piecemeal.
A 'master install kit' includes everything needed to set up a new ring and pinion. Contents typically:
Bearings:
Races (cups for the bearings):
Seals:
Preload control:
Shims:
Hardware:
Setup tools (sometimes):
Do NOT buy gears without a master kit. Cheap kits skip bearings or include used races, which always cost more in problems than the kit saves.
Buying piecemeal is also possible — pinion bearings from Timken, carrier bearings from KOYO, seals from National. Adds up to about the same money but introduces brand mismatching.
For a Dana 30 install: Yukon YK D30, Motive MK D30, USA Standard ZK D30. All include the same essential contents; brands vary slightly.
Upgrade option: solid pinion spacer kits (Yukon, Nitro). Replaces crush sleeve. Requires shimming for preload but is reusable and more accurate. $25-50 add-on. Worth it for any rebuilder who plans to set up gears repeatedly.
| Part | Vendor | Est. price |
|---|---|---|
| Yukon master install kit (any axle) | Yukon | ~$250 |
| Yukon solid pinion spacer upgrade | Yukon | ~$40 |
Written and maintained by an AZ wheeler and driveway wrencher. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.